Sound-conveying device for talking-machines.



E. R. JOHNSON.

SOUND CONVEYING DEVICE FCR TALKING MACHINES. APPL'ICATION FILED DEG. 24,1903` 1 ,01 5,32 l Patented Jan. S3, 191m.

l UNITED STATES PrlENT OFFICE.

ELDRIDGE R. JOHNSON, 0F PHILAELPHIA, PENNSYLVANIA, ASSIGNOR T0 VICTRTALKING MACHINE COMPANYyk A CORPORATION 0F NEW JERSEY.

SOUND-CUNVEYING DEVICE FOR TALKING-MACHINES:

Specification of Letters Patent.

Patented Jan. 23, 191%.

Application led December 24, 1903. Serial No. 186,482.

which the following is a full, clear, and

complete disclosure.

The object of my invention is to provide such a construction inconnection with sound tubes of talking machines that the sounds producedmay be modified andA purified, thereby particularly adapting 'saidmachinesfor the reproduction of speech and conversation, and isparticularly adapt-A ed to those machines where the sound tubes areplaced directly in or at the ear of the person listening to the -soundsproduced by said machine.

The sound produced by the disk type of talking machine is of such avolume and K character when conveyed directly to the ear through. theusual ear tube that it is necessary to reduce the volume and purify thetone to prevent the annoying and undesirable vibrations from beingobjectionable. This is accomplished by providing means for. selectingthe desirable and useful vibrations required, and allowing only such tobe conveyed to the ear. In this instance the means comprise a damper orwhat may be called an acoustic filter which is inserted at a suitablepoint in the sound conveying means such -point being preferably that atwhich thehollow sound box carrying arlnis pivoted to its support.Machilies having this feature of construction are particularly adaptedfor the reproduction of conversation or speech which is required inteaching foreign languages by means of records having distinct lessonsin such language or` languages recorded thereon. In the latter use oftalking machines it is essential and .necessary that the articulationandv pronunciation be very clearly reproduced without regard toI thevolume, although it isof course, required to have the volume orintensity of the words reproduced sufficiently great to be easily heard.This result, the present invention accomplishes in a most successful andeilicient mannen A For a full, clear and exact description of oneembodiment of mynin'vention reference s a part thereof, in which- Figurel represents a -side elevation of a talking machine having myimprovements applied thereto; Fig. 2 a plan view partly in section ofthe hollow sound arm audits supporting pivot or trunnion; and Fig. 3 an,enlarged elevation, partly in section, of? the sound tube at its pointof support, and showing my improved damper or acoustic lter in positiontherein.

Referring to the drawingl indicates the usual motor Casing havingrotatively mounted thereon the turntable 2, which carries the soundrecord 3. Mounted above said turnt-able and record 'is a hollow arm Ltcarrying the usual sound bor 5 which inconnection with the recordreproduces the sound. The

-hollow arm 4f has a bend 6 at its outer end with which the sound box 5is connected so that the diaphragm is practically in a plane parallelwith the said tube. rl'lie other end of said tube has an upward bend orcurvedv portion- 7 which extends practically vertically at right.langles to the main portion fi and is telescopically connected with anoutwardly curved elbow 8. The parte ofthe telescopic joint between thesections '7 and 8 are held in engagement in any suitable or well knownmanner, such as by having a tight t which holds the parts in engagementfrictionally or by providing the parts with screw threads. To vthis partof the tube 8 the usual flexible sonndconveying tube 9 may be connected.This tube 9 is preferably 'made of rubber and hasnt its end the wellknown ear pieces for 'entering or contact-ing with the ear. Thetelescopic portion of the' tube 8 which` connects with the portion 7 isformed by enlarging the lend of said tube 8 as indicated-at 10 so thatits internal diameter is substantially' the same as 'the externaldiameter of the part 'i' of the tube/4. This enlargeinentrl forms aslight shoulder 1l' which acts inl the nature ofa ,flange or-seatagainst which af diaphragm'lf may rest'andv be held in pol' sition. `Thediaphragm l2 is .referably' made of elastic, flexible material, softrubber and is held in position-against said shoulder 11 by means of aflexible ring 13 of metal or othersuitable material. The enlargedportion l() is provided with horizontal pivots or trunnions le: whichfifi liti

such. as

. other part of said tube.

said shoulder, and a fiexible ring for holding" said diaphragm seatedupon said shoulder.

8. In a talking machine, the combination of a soundreproducer, a soundconducting tube having an interior Acircumferential shoulder, adiaphragm seated against said shoulder, and fiexible means for holdingsaid diaphragm in position.

9. In a talking machine, the combination of'a sound reproducer, a soundConduct-ing tube provided with a joint therein having an interiorshoulder and-a diaphragm disposed intermediate of the ends of said tubel and arranged to be held in position between the parts of said jointagainst said shoulder, and arranged .to` transform the sound Wavesreceived 1n one part ofv saidtube and dlreot said transformed Wavesthrough the Scopoally 'connected with said arm, at 'the end Oppositesaid reproducer, and an elastic y lim erforate diaphragm extendin acrosssai tube at said, connection remote rom the diaphragm in said reproducerand formi-ng an inclosed chamber therewith and an opposed open chamberin said tube.

" Inwitness whereof I havehereunto set my hand this 21st day ofDecember, A. D.,

ELDRIDGE R. JOHNSON. Vitnesses:

` FREDK. C. EBERHARDT,

CHAs/K. BENNETT.

